Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 261834
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
134 PM EST MON JAN 26 2015

.SYNOPSIS...
A NOR`EASTER DEVELOPS OFF THE DELMARVA COAST THIS AFTERNOON AND
TRACKS SLOWLY NORTH TONIGHT AS IT INTENSIFIES REACHING JUST EAST OF
MONTAUK POINT BY TUESDAY NIGHT. THE STORM WEAKENS AS IT MOVES EAST
TO THE GULF OF MAINE ON WEDNESDAY. HIGH PRESSURE ON THURSDAY IS
FOLLOWED BY A CLIPPER LOW PASSING ACROSS THURSDAY NIGHT INTO EARLY
FRIDAY. COLD HIGH PRESSURE BUILDS IN FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE LOW WAS REDEVELOPING N OR CAPE HATTERAS AT 1 PM. SNOW WAS
BEGINNING TO INTENSIFY FROM NJ INTO THE CITY AND LONG ISLAND.
ELSEWHERE THE SNOW WAS LGT.

UP TO 4 INCHES BY DARK EXPECTED FOR THE SRN TIER OF THE CWA WITH
UP TO 2 ACROSS THE NRN TIER ATTM.

WINDS ARE ALREADY AROUND 30KT AT 44017...WITH MID 20S AT KFOK.

THE STORM APPEARS ON TRACK. THE 12Z GFS IS AN OUTLIER FROM THE 12Z
NAM AND 12Z ECMWF. HAVE UPPED SNOWFALL TOTALS ACCORDINGLY WITH
MOST AREAS IN THE 20-30 RANGE FOR THIS EVENT.

TEMPS ARE RUNNING WELL BLW GUIDANCE...SO MANUAL ADJUSTMENTS WERE
MADE TO THE GRIDS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
A LIFE THREATENING...POTENTIALLY HISTORIC WINTER STORM EXPECTED
FROM LATE TODAY INTO TUESDAY...

STILL ANTICIPATE THE LOW TO UNDERGO RAPID INTENSIFICATION AS THE
PARENT UPPER LOW CUTS OFF ALOFT NEAR THE MID ATLANTIC COAST
TONIGHT. THE LOW STALLS SE OF MONTAUK LATE TONIGHT INTO TUESDAY. A
PROLONGED PERIOD OF MODERATE TO HEAVY SNOW IS EXPECTED ON THE NW
FLANK OF THE LOW...IN THE DEFORMATION ZONE. THE MID LEVEL LOW
CENTERS AND INTENSE MID LEVEL FRONTOGENESIS WILL PROMOTE HEAVY
SNOW BANDS...BUT IT IS IMPOSSIBLE TO PREDICT THEIR LOCATION THIS
FAR OUT. MODELS ALSO HAVE A TENDENCY TO NOT SPREAD THE BEST LIFT
FAR ENOUGH NW IN INTENSE CYCLONES.

SNOWFALL RATES OF 2-4 INCHES PER HOUR EXPECTED LATE TONIGHT INTO
TUE MORNING.

SNOWFALL TOTALS WERE INCREASED SLIGHTLY PER THE 12Z DATA TO A
GENERAL 20-30 E OF THE HUDSON.

IN ADDITION...THE DEEP LOW PRESSURE COMBINED WITH STRONG HIGH
PRESSURE TO THE NORTH AND WEST AND HEAVY FALLING/BLOWING SNOW WILL
CREATE BLIZZARD CONDITIONS ACROSS THE ENTIRE REGION. A BLIZZARD
WARNING REMAINS IN EFFECT...WITH POTENTIAL FOR SUSTAINED WINDS UP
TO 35 MPH ON LONG ISLAND...AND WIND GUSTS RANGING FROM 40 MPH
INLAND...TO 45-50 MPH MOST ELSEWHERE. GUSTS UP TO 60 MPH CANNOT BE
RULED OUT ACROSS FAR EASTERN LONG ISLAND.

WITH THE LOW NEARLY STALLING NEAR CAPE COD ON TUESDAY...LIGHT TO
OCCASIONALLY MODERATE SNOW IS POSSIBLE IN MESOSCALE
BANDS...ESPECIALLY LATE TUESDAY MORNING INTO EARLY AFTERNOON.

TEMPS DURING THE STORM WILL GENERALLY BE IN THE 20S...EXCEPT
FALLING TO 15-20 TONIGHT INLAND. WIND CHILLS WILL BE MOSTLY IN
THE SINGLE DIGITS TO MID TEENS...BUT COULD GET CLOSE TO ZERO ACROSS
SOUTHERN CT. TEMPERATURES ON TUESDAY WILL ONLY BE IN THE LOWER TO
MIDDLE 20S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE NOR`EASTER BEGINS TO FILL AND PULL AWAY TUESDAY NIGHT. LIGHT
SNOW ENDS FROM WEST TO EAST WITH AN INCH OR LESS OF ADDITIONAL
ACCUMULATION. WINDS ALSO DIMINISHING AND HAVE REMOVED MENTION OF
BLOWING SNOW.

BECOMING SUNNY ON WEDNESDAY WITH 15-20 MPH WINDS. TEMPS FCST BELOW
MOS WITH SNOW COVER. WIND CHILLS ON WEDNESDAY ARE IN THE LOWER
TEENS.

CONTINUE TO UNDERCUT MOS THROUGH THE PERIOD WITH THE NEW SNOW COVER.

CLIPPER SYSTEM STILL ON TAP FOR THURSDAY NIGHT INTO FRIDAY MORNING.
THIS LOOKS LIKE A "TYPICAL" CLIPPER WITH 1-3" IN AN ALL SNOW EVENT.

HIGH PRESSURE BUILDS BACK IN ON SATURDAY WITH BELOW NORMAL
TEMPERATURES CONTINUING.

THE ACTIVE PATTERN REACHING THE LIMITS OF PREDICTABILITY BY SUNDAY.
SUGGESTION OF A SOUTHERN STREAM SYSTEM SOMETIME LATE THIS WEEKEND
INTO EARLY NEXT WEEK.  WITH GEFS LOOKING VERY CHAOTIC...HARD TO SAY
MUCH AS TO WHAT MIGHT HAPPEN WITH THIS NEXT SYSTEM.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
** HIGH IMPACT SNOW AND WIND EVENT EXPECTED FROM LATE TODAY INTO
TUESDAY NIGHT **

LOW PRESSURE DEVELOPING OFF THE MID ATLANTIC COAST IS EXPECTED TO
TRACK SOUTH AND EAST OF THE REGION TONIGHT.

MAINLY IFR CONDITIONS IN SNOW THROUGH 18Z...THEN LIFR CONDITIONS
GRADUALLY DEVELOPING BY 21Z FROM S TO N. BLIZZARD CONDITIONS EXPECTED
AT KJFK/KLGA/KISP/KGON BY LATE THIS EVENING. 1-3" OF SNOW EXPECTED
BY 00Z...THEN 2-4 INCH AN HOUR RATES DEVELOP FROM SE TO NW STARTING
AROUND MIDNIGHT.

NE WINDS STRENGTHEN WITH GUSTS 25-30KT BY MID-LATE AFTERNOON. WINDS
BACK TO THE NNE LATE TONIGHT...WITH GUSTS INCREASING TO
25-40KT...LOWEST FAR W TERMINALS AND STRONGEST FAR E TERMINALS.

MODERATE ICING IS LIKELY BELOW FL180. MODERATE TURBULENCE BETWEEN
SFC-FL390 WITH LOCAL SEVERE POSSIBLE FL200-310. REFER TO ZNY MIS AND
SIGMET VICTOR FOR MORE INFORMATION.

     NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT:  HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KJFK FCSTER COMMENTS: CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW
BANDS THIS AFTERNOON. 1-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER
00Z...HEAVY SNOW WITH RATES OF 2-4 INCHES PER HOUR LIKELY.

KLGA FCSTER COMMENTS: CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW
BANDS THIS AFTERNOON. 1-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER
00Z...HEAVY SNOW WITH RATES OF 2-4 INCHES PER HOUR LIKELY.

KEWR FCSTER COMMENTS: CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW
BANDS THIS AFTERNOON. 1-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER
00Z...HEAVY SNOW WITH RATES OF 2-4 INCHES PER HOUR LIKELY.

KTEB FCSTER COMMENTS: CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW
BANDS THIS AFTERNOON. 1-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER
00Z...HEAVY SNOW WITH RATES OF 2-4 INCHES PER HOUR LIKELY.

KHPN FCSTER COMMENTS: TIMING OF GUSTS MAY BE OFF BY AN HOUR OR TWO.
CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW BANDS THIS AFTERNOON.
1-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER 00Z...HEAVY SNOW WITH
RATES OF 2-4 INCHES PER HOUR LIKELY.

KISP FCSTER COMMENTS: CONDITIONS MAY BRIEFLY DROP TO LIFR IN SNOW
BANDS THIS AFTERNOON. 2-3 INCHES OF SNOW EXPECTED THROUGH 00Z. AFTER
00Z...HEAVY SNOW WITH RATES OF 2-4 INCHES PER HOUR LIKELY.


.OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...
.TUESDAY AND TUESDAY EVENING...LIFR OR LOWER CONDITIONS WITH
BLIZZARD CONDITIONS. NE-N WINDS G35-50 KT.
.LATE TUESDAY NIGHT...GRADUALLY BECOMING VFR. NW WINDS G25-35KT.
.WEDNESDAY...VFR. NW WINDS G25-30KT POSSIBLE.
.WEDNESDAY NIGHT-THURSDAY...VFR.
.THU NGT...MVFR OR LOWER CONDITIONS IN LGT SN.
.FRI...CHC MVFR IN LGT SN IN THE AM. VFR WITH NW WNDS G25-30KT IN
THE AFTN.

&&

.MARINE...
NO CHANGES TO THE MARINE HEADLINES WITH THIS FORECAST PACKAGE.
HAVE MADE MINOR ADJUSTMENTS TO WINDS AND SEAS.

WINDS AND SEAS INCREASE ACROSS ALL WATERS ON TODAY AHEAD OF
APPROACHING LOW PRESSURE. GALE FORCE EASTERLY WIND GUSTS EXPECTED
ON THE OCEAN WATERS DURING THE DAY...RAMPING UP TONIGHT AS WINDS
BACK NORTHERLY TO MINIMAL HURRICANE FORCE ON THE EASTERN OCEAN
WATERS LATE MON NIGHT INTO TUE MORNING...AND STORM FORCE ELSEWHERE
AND ALSO ON EASTERN LONG ISLAND SOUND AND THE BAYS OF LONG ISLAND.
THE EASTERN OCEAN WATERS MAY ALSO SEE SUSTAINED STORM FORCE WINDS
DURING THIS TIME.

WINDS AND SEAS START SUBSIDING TUESDAY NIGHT. EXPECT TO BE BELOW
GALES BEFORE MORNING AND BELOW SCA LEVELS IN THE EARLY EVENING
TUESDAY.

SUB SCA ON THURSDAY INTO EARLY FRIDAY MORNING. THEN SCA WINDS RETURN
AS A CLIPPER SYSTEM DEEPENS WELL OFF SHORE.

&&

.HYDROLOGY...
A MAJOR SNOWSTORM EXPECTED FROM MON INTO TUE NIGHT...WITH LIQUID
EQUIVALENT AMOUNTS OF 1.5 TO 2.25 INCHES.

LIQUID EQUIVALENT PRECIPITATION AMOUNTS FOR THE SYSTEM MOVING
THROUGH THURSDAY NIGHT INTO FRIDAY IS CURRENTLY FORECAST TO BE
LIGHT...MOSTLY IN THE FORM OF SNOW.

ICE ON THE WALLKILL AND YANTIC RIVERS IS CAUSING MINOR
FLUCTUATIONS IN RIVER LEVELS AT THIS TIME.

&&

.TIDES/COASTAL FLOODING...
A COASTAL FLOOD WARNING IS IN EFFECT FOR NORTHERN LONG ISLAND AND
WESTERN NY COAST WITHIN THE WESTERN LONG ISLAND SOUND.

FOR THE TWIN FORKS OF LONG ISLAND...COASTAL FLOOD WARNING IS IN
EFFECT.

A COASTAL FLOOD WARNING FOR THE SOUTH SHORE BAYS OF LONG ISLAND.

COASTAL FLOOD ADVISORY IS IN EFFECT FOR NY HARBOR...AND THE CT
COASTS.

THE NOR`EASTER IS EXPECTED TO PRODUCE MODERATE COASTAL IMPACTS FOR
PARTS OF THE REGION OVERNIGHT INTO EARLY TUESDAY MORNING HIGH TIDE.
THERE`S THE POTENTIAL FOR FLOODING OF VULNERABLE SHORE ROADS AND/OR
ADJACENT PROPERTIES DUE TO HEIGHT OF STORM TIDE AND/OR WAVE ACTION.

THE UNCERTAINTY WITH THE SURGE IS IN HOW QUICKLY WINDS TURN FROM
THE NE TO N. AN EARLIER VEERING OF WINDS TO THE N AHEAD OF HIGH
TIDE TYPICALLY REDUCES SURGE IN OUR REGION.

THE MOST LIKELY SURGE FOR COASTAL AREAS IS:

- WESTERN LONG ISLAND SOUND (NY ZONES)...3 TO 4 FT OF SURGE WITH
POTENTIAL FOR UP TO 4 1/2 FT.

- LONG ISLAND SOUND CT COAST...2 TO 2 1/2 FT OF SURGE WITH POTENTIAL
FOR UP TO 3 FT.

- THE TWIN FORKS OF LONG ISLAND WHERE 3 TO 4 FT OF SURGE IS POSSIBLE
AS WATER GETS PILED UP AROUND THE FORKS.

- NEW YORK HARBOR AND THE SOUTH SHORE BAYS...2 TO 3 FT OF SURGE.

BEACH EROSION AND WASHOVERS ARE EXPECTED ALONG OCEAN FACING BARRIER
BEACHES OF LONG ISLAND DUE TO 7 TO 12 FT WAVES AND THE HIGH STORM
TIDE. A FEW EXPOSED WATERFRONT STRUCTURES MAY BE DAMAGED.

HIGH WAVES AND HIGH STORM TIDE WILL ALSO CAUSE BEACH EROSION ALONG
NORTH FACING SHORELINES OF LONG ISLAND SOUND AND ALONG THE TWIN
FORKS. A FEW EXPOSED WATERFRONT STRUCTURES MAY BE DAMAGED.

&&

.CLIMATE...
THIS BLIZZARD HAS THE POTENTIAL TO PRODUCE THE LARGEST SINGLE-
STORM SNOWFALL IN NYC HISTORY. HERE ARE THE CURRENT TOP TEN
SNOWFALLS FOR THE CITY...


AMOUNT        DATES

26.9          FEB 11-12 2006
25.8          DEC 26-27 1947
21.0          MAR 12-13 1888
20.9          FEB 25-26 2010
20.2          JAN 7-8   1996
20.0          DEC 26-27 2010
19.8          FEB 16-17 2003
19.0          JAN 26-27 2011
18.1          JAN 22-24 1935 AND MARCH 7-8 1941
18.0          DEC 26    1872

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR
     CTZ005>012.
     COASTAL FLOOD ADVISORY FROM 1 AM TO 7 AM EST TUESDAY FOR
     CTZ009>012.
NY...COASTAL FLOOD WARNING FROM 1 AM TO 7 AM EST TUESDAY FOR NYZ079-
     081.
     BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR
     NYZ067>075-078>081-176>179.
     COASTAL FLOOD WARNING FROM MIDNIGHT TONIGHT TO 5 AM EST
     TUESDAY FOR NYZ075-080-178-179.
     COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EST
     TUESDAY FOR NYZ072-074.
     COASTAL FLOOD WARNING FROM 3 AM TO 7 AM EST TUESDAY FOR NYZ071-
     073-078-176-177.
NJ...BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR NJZ002-
     004-006-103>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ345.
     STORM WARNING FROM 6 PM THIS EVENING TO 6 PM EST TUESDAY FOR
     ANZ330-340-345-353-355.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 PM EST TUESDAY FOR
     ANZ335-338.
     GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ350-353-355.
     HURRICANE FORCE WIND WARNING FROM 6 PM THIS EVENING TO NOON
     EST TUESDAY FOR ANZ350.

&&

$$
SYNOPSIS...DS/JST
NEAR TERM...JMC
SHORT TERM...JMC/DS
LONG TERM...JST
AVIATION...MMD
MARINE...DS/JST
HYDROLOGY...DS/JST
TIDES/COASTAL FLOODING...PW
CLIMATE...









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